Data on the concentrations of etoposide, PSC833, BAPTA-AM, and cycloheximide that do not compromise the vitality of mature mouse oocytes, parthenogenetically activated and fertilized embryos

AbstractThese data document the vitality of mature mouse oocytes (Metaphase II (MII)) and early stage embryos (zygotes) following exposure to the genotoxic chemotherapeutic agent, etoposide, in combination with PSC833, a selective inhibitor of permeability glycoprotein. They also illustrate the vitality of parthenogenetically activated and fertilized embryos following incubation with the calcium chelator BAPTA-AM (1,2-Bis(2-aminophenoxy)ethane- N,N,N′,N′-tetraacetic acid tetrakis (acetoxymethyl ester)), cycloheximide (an antibiotic that is capable of inhibiting protein synthesis), and hydrogen peroxide (a potent reactive oxygen species). Finally, they present evidence that permeability glycoprotein is not represented in the proteome of mouse spermatozoa. Our interpretation and discussion of these data feature in the article “Identification of a key role for permeability glycoprotein in enhancing the cellular defense mechanisms of fertilized oocytes” (Martin et al., in press) [1]

Finding Needles in Haystacks: The Use of Quantitative Proteomics for the Early Detection of Colorectal Cancer

Colorectal cancer (CRC) is a common and treatable disease if diagnosed early. Current population screening programs are suboptimal, and consequently, there is a need for the development of new methodologies for early diagnosis of CRC. In the past 10 years, unprecedented technological advancements in the field of mass spectrometry (MS)-based proteomics have progressively increased the sophistication and utility of these investigations, leading to the draft mapping of the human proteome. These exciting studies have shaped our mechanistic understanding of the human genome and begun to provide us with a suite of novel biomarkers to predict the onset, progression and severity of many debilitating diseases. Thus, sophisticated MS workflows coupled with revolutionary protein quantification techniques hold promise for the field of MS-based plasma proteomics, particularly valuable in the context of early stage identification of curable CRC. However, within the last 40 years, no new plasma protein biomarkers of CRC have been translated into clinical practice. Here. we discuss the application of proteomic technologies within the field of CRC, highlighting contemporary MS-based plasma proteomic strategies that could be exploited to deliver on the promise of a panel of sensitive and specific plasma-based biomarkers with which to non-invasively detect early stage CRC

Mechanisms of tethering and cargo transfer during epididymosome-sperm interactions

Abstract Background The mammalian epididymis is responsible for the provision of a highly specialized environment in which spermatozoa acquire functional maturity and are subsequently stored in preparation for ejaculation. Making important contributions to both processes are epididymosomes, small extracellular vesicles released from the epididymal soma via an apocrine secretory pathway. While considerable effort has been focused on defining the cargo transferred between epididymosomes and spermatozoa, comparatively less is known about the mechanistic basis of these interactions. To investigate this phenomenon, we have utilized an in vitro co-culture system to track the transfer of biotinylated protein cargo between mouse epididymosomes and recipient spermatozoa isolated from the caput epididymis; an epididymal segment that is of critical importance for promoting sperm maturation. Results Our data indicate that epididymosome-sperm interactions are initiated via tethering of the epididymosome to receptors restricted to the post-acrosomal domain of the sperm head. Thereafter, epididymosomes mediate the transfer of protein cargo to spermatozoa via a process that is dependent on dynamin, a family of mechanoenzymes that direct intercellular vesicle trafficking. Notably, upon co-culture of sperm with epididymosomes, dynamin 1 undergoes a pronounced relocation between the peri- and post-acrosomal domains of the sperm head. This repositioning of dynamin 1 is potentially mediated via its association with membrane rafts and ideally locates the enzyme to facilitate the uptake of epididymosome-borne proteins. Accordingly, disruption of membrane raft integrity or pharmacological inhibition of dynamin both potently suppress the transfer of biotinylated epididymosome proteins to spermatozoa. Conclusion Together, these data provide new mechanistic insight into epididymosome-sperm interactions with potential implications extending to the manipulation of sperm maturation for the purpose of fertility regulation

Probing the Origins of 1,800 MHz Radio Frequency Electromagnetic Radiation Induced Damage in Mouse Immortalized Germ Cells and Spermatozoa in vitro

As the use of mobile phone devices is now highly prevalent, many studies have sought to evaluate the effects of the radiofrequency-electromagnetic radiation (RF-EMR) on both human health and biology. While several such studies have shown RF-EMR is capable of inducing cellular stress, the physicobiological origin of this stress remains largely unresolved. To explore the effect of RF-EMR on the male reproductive system, we exposed cultured mouse spermatogonial GC1 and spermatocyte GC2 cell lines, as well as cauda epididymal spermatozoa to a waveguide generating continuous wave RF-EMR (1.8 GHz, 0.15 and 1.5 W/kg). This study demonstrated that a 4 h exposure is capable of inducing the generation of mitochondrial reactive oxygen species (ROS) in populations of GC1 (7 vs. 18%; p < 0.001) and GC2 cells (11.5 vs. 16 %; p < 0.01), identifying Complex III of the electron transport chain (ETC) as the potential source of electrons producing ROS. Assessing the generation of ROS in the presence of an antioxidant, penicillamine, as well as measuring lipid peroxidation via 4-hydroxynonenal levels, indicated that the elevated incidence of ROS generation observed under our exposure conditions did not necessarily induce an overt cellular oxidative stress response. However, exposure to RF-EMR at 0.15 W/kg for 3 h did induce significant DNA fragmentation in spermatozoa (that was no longer significant after 4 h), assessed by the alkaline comet assay (p < 0.05). Furthermore, this fragmentation was accompanied by an induction of oxidative DNA damage in the form of 8-hydroxy-2′-deoxyguanosine, which was significant (p < 0.05) after spermatozoa were exposed to RF-EMR for 4 h. At this exposure time point, a decline in sperm motility (p < 0.05) was also observed. This study contributes new evidence toward elucidating a mechanism to account for the effects of RF-EMR on biological systems, proposing Complex III of the mitochondrial ETC as the key target of this radiation

Intron Dynamics in Ribosomal Protein Genes

The role of spliceosomal introns in eukaryotic genomes remains obscure. A large scale analysis of intron presence/absence patterns in many gene families and species is a necessary step to clarify the role of these introns. In this analysis, we used a maximum likelihood method to reconstruct the evolution of 2,961 introns in a dataset of 76 ribosomal protein genes from 22 eukaryotes and validated the results by a maximum parsimony method. Our results show that the trends of intron gain and loss differed across species in a given kingdom but appeared to be consistent within subphyla. Most subphyla in the dataset diverged around 1 billion years ago, when the “Big Bang” radiation occurred. We speculate that spliceosomal introns may play a role in the explosion of many eukaryotes at the Big Bang radiation

Riesgo de accidente cerebrovascular en pacientes con aterosclerosis carotídea asintomática: ¿se debe tratar médicamente o quirúrgicamente?

Cerebrovascular disorders remain the leading cause of neurological morbidity and mortality in the world, representing one of the pathological entities responsible for the greatest burden of disease worldwide. Carotid atherosclerosis or stenosis is a potential risk factor for ischemic stroke. The identification and strict follow-up of this condition are essential in the secondary prevention of complications through primary care and the specialized treatment of cardiometabolicrisk. However, depending on this risk and/or presence of symptoms, definitive treatment is necessary. Currently, there is controversy as to whether asymptomatic carotid stenosis is better to be treated medically or surgically. Consideringthe significance of such entity, this review aims to analyze recent evidence on the risk of ischemic stroke in the case of asymptomatic carotid atherosclerosis among adults, as well as the potential benefit of the surgical vs. pharmacologicaltreatment for this condition. For this purpose, a literature search for publications up to 2023 was carried out in PubMed, ScienceDirect, Web of Science and MEDLINE databases. It was shown that there is a significant risk of stroke associated with asymptomatic carotid stenosis (> 10 % approximately), even in patients with active antiplatelet and lipid-lowering therapy. Out of all those who receive medical treatment, around 80 % had a five-year survival rate. However, stenosisprogression occurs on average in more than 60 % of the cases and is significant. On the other hand, carotid stenting and endarterectomy are curative interventions. Nevertheless, these procedures involve a higher risk compared to the medicaltherapy during the peri- and postoperative period, as well as 30 days afterwards, due to the occurrence or recurrence of stroke, acute myocardial infarction or death from any cause. Despite this, the use of endarterectomy has shown superiorlong-term benefits concerning these same outcomes. Thus, evidence regarding the superiority of surgical treatment compared to pharmacological treatment for asymptomatic carotid atherosclerosis or stenosis is heterogeneous. However, it seems that surgical treatment, specifically endarterectomy, could have a significant impact on the occurrence orrecurrence of ipsilateral stroke and death in the long term but with controversial peri- and postoperative outcomes.Los desórdenes cerebrovasculares siguen siendo la primera causa de morbilidad y mortalidad neurológica en el mundo, representando una de las entidades patológicas que genera mayor carga de enfermedad a nivel global. La aterosclerosis,o estenosis carotídea, es un potencial factor de riesgo para el ictus isquémico. La identificación y seguimiento estricto de esta condición son esenciales en la prevención secundaria de complicaciones a través de la atención primaria yel manejo especializado del riesgo cardiometabólico. No obstante, dependiendo de este riesgo y/o la presencia de sintomatología, es necesario realizar un manejo definitivo. Actualmente, existe controversia sobre si es mejor tratar la estenosis carotídea asintomática, ya sea médica o quirúrgicamente. Teniendo en cuenta la relevancia de esta entidad, elobjetivo de esta revisión consiste en analizar la evidencia reciente sobre el riesgo de ictus isquémico en la aterosclerosis carotídea asintomática en adultos, y el potencial beneficio del manejo quirúrgico vs. farmacológico de esta condición.Para esto, se llevó a cabo una búsqueda bibliográfica en las bases de datos PubMed, ScienceDirect, Web of Science y MEDLINE, hasta el año 2023. Se evidenció que el riesgo de ictus asociado a estenosis carotídea asintomática es significativo (>10 %, aproximadamente), incluso en aquellos con terapia antiplaquetaria e hipolipemiante activa. En aquellos con manejo médico, la supervivencia a cinco años es alrededor del 80 %. Sin embargo, la progresión de la estenosis sucede en promedio en más del 60 % de los casos, y es significativa. Por el contrario, el stent carotídeo y la endarterectomía son intervenciones resolutivas. Pero existe un riesgo mayor comparado con la terapia médica, el cual se atribuye al periodoperi- y posoperatorio, así como a 30 días de aparición o recurrencia del ictus, infarto agudo de miocardio o muerte por cualquier causa; aunque el uso de la endarterectomía ha demostrado beneficios superiores a largo plazo en cuanto a estos mismos desenlaces. Entonces, la evidencia es heterogénea en cuanto a la superioridad del tratamiento quirúrgicocomparado con la terapia farmacológica en el manejo de la aterosclerosis o estenosis carotídea asintomática. Sin embargo, parece ser que el manejo quirúrgico, específicamente la endarterectomía, podría impactar significativamente sobre la aparición o recurrencia del ictus ipsilateral y muerte a largo plazo, pero con resultados controversiales peri- ypostoperatorios